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Altera_Forum
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13 years ago

niosII in port data read problem

HI,I want to read in port data ,but I can't read correct value :( I use i=IORD(IN_PIO_BASE, 0); printf(" %d %d",IORD(IN_PIO_BASE, 0),i); Regardless of the input 1 or 0,it al...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The function you are using seems to be reasonable. There are many possibilities to your problem.

Make sure:

1. The physical pin is assigned properly in your Quartus project (correct location, voltage standard).

2. The pin assignment in your top level design is connected to the proper path to your SOPC or Q-SYS instantiation.

3. The base address (IN_PIO_BASE) directly corresponds to the expected value in SOPC or Q-SYS.

If you have looked at all of these and you are 100% sure they are correct, begin testing at the firmware level to make sure your pin is behaving properly. (tie it to an LED or use signaltap to monitor). Also, you can try hard-coding the input to SOPC/Q-SYS to a '1' or '0' and make sure software reads the proper value.